struct S {
  v: i32,
}

impl Drop for S {
  fn drop(&mut self) {
    println!("This is an S structure with value {}: so long, and thanks for all the fish!", self.v)
  }
}

fn main() {
  let s1 = S{v: 1};
  let s3 = S{v: 3};
  let rs = &s3;

  println!("Start of main, {} is on the stack!", s1.v);
  println!("{} is also here...", s3.v);
  {
    let s2 = S{v: 2};

    println!("Inner block: {} is on the stack!", s2.v);
  }

  println!("{} is still there...", rs.v);
  println!("{} is still there...", s1.v)
}